1. Field of the Invention
The present invention relates to a transmission assembly and a wheel thereof, and more particularly to a transmission assembly and a wheel thereof with a replaceable tire skin.
2. Related Art
Generally speaking, a robot cleaner on market uses wheels as a mobile mechanism thereof. A tire skin of the wheel of the robot cleaner is normally made of rubber. Whenever the wheel rotates, the tire skin is worn by abrasion of varying degrees at the same time. Specifically, the tire skin is consumable, so that a user needs to replace the tire skin of the wheel regularly to keep the wheel rotating normally as not to slip.
Currently, in a joining method of the tire skin and a wheel frame of the robot cleaner, fixation is achieved by mold double injection. Specifically, the wheel frame and the tire skin are integrally formed by double injection, so that the combination of the wheel frame and the tire skin is fairly stable. But for the joining method of mold double injection, the production cost is too high, and when the tire skin is worn, both the wheel frame and the tire skin have to be replaced at the same time, thus increasing the material cost.
In another conventional joining method of the tire skin and the wheel frame, fixation is achieved by press-fit. Specifically, the outer diameter of the tire skin is slightly smaller than the outer diameter of the wheel frame, and the tire skin is forced to be sleeved on the wheel, thus achieving a press-fit effect to fix the tire skin to the wheel frame. For the joining method, the production cost is low, and when the tire skin is worn, only the tire skin is required to be replaced, thus reducing the material cost. When the press-fit method is used, if the interference between the tire skin and the wheel frame is too large, although the combination of the tire skin and the wheel frame is very stable, it is more difficult for the tire skin to be mounted to the wheel frame, and the time required for replacing the tire skin of the wheel is relatively increased at the same time. In contrast, if the interference between the tire skin and the wheel frame is too small, although it is easier for the tire skin to be mounted to the wheel frame, the combination of the tire skin and the wheel frame is weak, thus causing the rotating wheel to slip easily.
Therefore, the conventional joining methods of the tire skin and the wheel frame do not have advantages of improved combination, lowered cost, and convenient assembly at the same time.